ClassFormatError when processors passed to Reflect.compile() produce new source files

[lukaseder]

When a processor passed to Reflect.compile() attempts to produce new source files, we get the following error:

Exception in thread "main" java.lang.ClassFormatError: Incompatible magic value 1885430635 in class file test/Data
	at java.base/java.lang.ClassLoader.defineClass1(Native Method)
	at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1016)
	at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:877)
	at org.joor.Compile$ByteArrayClassLoader.findClass(Compile.java:169)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:588)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
	at org.joor.Compile.lambda$compile$3(Compile.java:142)
	at org.joor.Compile$ClassFileManager.loadAndReturnMainClass(Compile.java:232)
	at org.joor.Compile.compile(Compile.java:141)
	at org.joor.Reflect.compile(Reflect.java:102)
	at org.jooq.annotation.processor.Test.main(Test.java:9)

Hi, @lukaseder!
+1 to this issue.
I also faced this issue, while trying to test my annotation processor with jOOR.
But I have another error... Kind of this:

Caused by: java.lang.RuntimeException: java.lang.UnsupportedOperationException
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.handleExceptions(JavacTaskImpl.java:163)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.doCall(JavacTaskImpl.java:100)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.call(JavacTaskImpl.java:94)
        at org.joor.Compile.compile(Compile.java:97)
        ... 67 more
Caused by: java.lang.UnsupportedOperationException
        at java.compiler@13.0.2/javax.tools.SimpleJavaFileObject.getCharContent(SimpleJavaFileObject.java:131)
        at jdk.compiler/com.sun.tools.javac.api.ClientCodeWrapper$WrappedFileObject.getCharContent(ClientCodeWrapper.java:661)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.readSource(JavaCompiler.java:613)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.parse(JavaCompiler.java:676)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.parseFiles(JavaCompiler.java:1031)
        at jdk.compiler/com.sun.tools.javac.processing.JavacProcessingEnvironment$Round.<init>(JavacProcessingEnvironment.java:1117)
        at jdk.compiler/com.sun.tools.javac.processing.JavacProcessingEnvironment$Round.next(JavacProcessingEnvironment.java:1153)
        at jdk.compiler/com.sun.tools.javac.processing.JavacProcessingEnvironment.doProcessing(JavacProcessingEnvironment.java:1392)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.processAnnotations(JavaCompiler.java:1263)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:935)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.lambda$doCall$0(JavacTaskImpl.java:104)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.handleExceptions(JavacTaskImpl.java:147)
        ... 70 more

Tested on Java 13, as you can see.

java -version

openjdk version "13.0.2" 2020-01-14

javax.tools.SimpleJavaFileObject#getCharContent just throws an exception and org.joor.Compile.JavaFileObject doesn't override this method and that's it.

[lukaseder]

Thanks, @JBreathe. Perhaps it's the same error, perhaps it isn't. To be sure, would you mind creating a new issue with a full example on how to reproduce this?

Sure, @lukaseder!

[onizucraft]

I'm having the same error as @lukaseder. Will probably fork and try to solve it.

[michael-schnell]

Same problem here ("java.lang.ClassFormatError: Incompatible magic value") while trying to test an annotation processor.

It seems that the source code generated by the annotation processor is interpreted as byte code. In ByteArrayClassLoader the return defineClass(name, bytes, 0, bytes.length) method fails, because the bytes array has the source and not class byte code. So the failing "magical number" is actually representing the first bytes of the source code created by the annotation processor.